Base station



FIG. 1 is a perspective view of a base station;

FIG. 2 is a front-elevational view thereof;

FIG. 3 is a right, side-elevational view thereof, the left,side-elevational view being a mirror image of the right,side-elevational view;

FIG. 4 is a top, plan view thereof; and,

FIG. 5 is a bottom, plan view thereof.

The ornamental design for a base station, as shown and described.